Insulated clamp



R. S. DEAL INSULATED CLAMP Dec. 1, 1964 Filed July 25, 1960 INVENTOR. ROBERT s. DEAL BY M ATTORNEYS 3,159,7ll8 INSULATED CLAM? Robert S. Deal, Los Altos, CalirI, assignor to Raychen Corporation, Redwood ity, Calih, a corporation of California Filed July 25, 1960, Ser. No. 45,061 3 Claims. (Cl. 174 m) This invention relates to clamping devices and has particular reference to an electrically insulated clamp for supporting electrical cables, wire bundles and the like.

A primary object of the present invention is to provide a novel clamping device provided with insulation means.

A further object of the present invention is toprovide a novel clamp formed from a single length of insulationcovered metal. I 4 Another object of the present invention is to provide a novel process for forming an insulated clamp.

Other objects and advantages of this invention it is believed will be readily apparent from the following detailed description of a preferred embodiment thereof when read in connection with the accompanying drawings.

In the drawings: 7

FIGURE 1 is a fragmentary perspective view of the blank from which the. clamp of the present invention is fabricated.

Patented Dec. 1,5954

chemically cross linked polymers such as polyethylene, etc., is disclosed in the copending application of Cook et al., Serial No. 43,230, filed July 15, 19 60 noWPat. No. 3,086,242 on Process and Apparatus for Producing Materials Having Plastic Memory. While such materials are preferred, other materials such as expanded vinyl plastic and various elastomers such as silicone rubber, neoprene rubber, etc., dipped or stretched onto the strip, can be used.

. The insulated strip illustrated in FIGURE 1 is readily formed, as in a punch press die, into the shape illustrated in FIGURE 2. As indicated above, the closed shape shown in FIGURE 3 is almost a perfect circle. In the use of the clamp in supporting wire bundles, the design,

of: the ic-shaped portion v functions as a wedge in pushing the wire bundle into the minimum circular area and eliminating pinching of the individual Wires as the clamp is closed down. The clamp thus provides a'strong,

stood that I do not wish to be limited to the details set FIGURE 2 is a side view of the clamp of the present invention illustrating the clamp in the open position.

FIGURE 3 is a view similar to FIGURE 2, but illustrating the clamp in the closed, installed position. Referring now to the drawings, the clamp 10 of the present invention comprises essentially a single, rectangular strip 11 of relatively thin metal encased in a sleeve or jacket 12 of insulation material. The strip 11 has a generally circular or cylindrical body portion, provided at one extremity with an outwardly oil-set portion 13 leading to an L-shaped portion 14. The otherextremity is provided with a mating L-shaped portion 15,'the outer, parallel legs and 21 of the respective L-shaped portions are joined to the body portion by connecting legs and are provided with apertures 22 and 23 for the reception of a bolt element24 whereby the clamp may be secured to a wall or other flat surface for supporting a bundle of wires (indicated by the phantom lines of FIGURE 3), or other objects. It will be seen that by virtue of the shape of the clamp, the body portion will, when in the closed position of FIGURE 3, form a virtually unbroken closed circle or cylindrical inner surface.

As indicated in FIGURE 1, the'clamp is initially in the form of a flat metal rectangle or strap having applied thereto the insulation jacket 12. The jacket is tightly aflixed to the strap by inserting the strap inside a suitable length of a sleeve of a heat-unstable plastic material, i.e., a material whichhas been pre-expanded'under condition such that it will shrink to its original diameter upon the application of heat. Thus, after insertion of the strap into the sleeve, which has an expanded diameter approximately equal to the width of the strap and an original diameter less than the cross-sectional perimeter of the strap, the assembly is heated to the shrink-back tempera; ture and the sleeve shrinks tightly onto the strap, form- ,ing the jacket 12.

The sleeve which ultimately forms the jacket 12 can be made from any plastic material having plastic memory properties. A process for producing such sleeving or tubing from polytetrafluorethylene and irradiated or forth, but my invention is of the full scope of the ap- I I pended claims.

I claim: I

1. An insulated clamp comprising a strip of metal having tightly applied thereto a heat-shrunk sleeve of a heat-unstable plastic-material, said clamp having a body portion and extremities, each of said extremities being generally L.'-shaped with an outerleg and a connecting leg joining said outer leg to said body portion, said extremities being relatively oriented for nesting thereof in clamping relationship, said connecting legs extending in a direction outwardly and away from the periphery of said body portion, a first one of said connecting legs being generally tangent to they periphery of said body portion, said connecting legs being substantially parallel and said outer legs being substantially parallel when said extremities are in clamping relationship, said first connecting leg being connected to said body portion at a first point and the second of said connecting legs being connected to said body portion at a second point, said first point and said second point being adjacent to each other when said extremities are in clamping relationship, said body portion forming a substantially circular shape when said first point is broughtadjacent to said second point by placing said extremities in clamping relationship and said extremities being adapted to be secured to each other while in clamping relationship.

2. The clamp of claim 1 wherein the outer leg connected to said second connecting leg is generally tangent to the periphery of said body portion.

3. The clamp of claim 1 wherein said first connecting leg is connected to said body portion by an oifset portion.

References Cited in the file of this patent V UNITED STATES PATENTS 

1. AN INSULATED CLAMP COMPRISING A STRIP OF METAL HAVING TIGHTLY APPLIED THERETO A HEAT-SHRUNK SLEEVE OF A HEAT-UNSTABLE PLASTIC MATERIAL, SAID EXTREMITIES BEING PORTION AND EXTREMITIES, EACH OF SAID EXTREMITIES BEING GENERALLY L-SHAPED WITH AN OUTER LEG AND A CONNECTING LEG JOINING SAID OUTER LEG TO SAID BODY PORTION, SAID EXTREMITIES BEING RELATIVELY ORIENTED FOR NESTING THEREOF IN CLAMPING RELATIONSHIP, SAID CONNECTING LEGS EXTENDING IN A DIRECTION OUTWARDLY AND AWAY FROM THE PERIPHERY OF SAID BODY PORTION, A FIRST ONE OF SAID CONNECTING LEGS BEING GENERALLY TANGENT TO THE PERIPHERY OF SAID BODY PORTION, SAID CONNECTING LEGS BEING SUBSTANTIALLY PARALLEL AND SAID OUTER LEGS BEING SUBSTANTIALLY PARALLEL WHEN SAID EXTREMITIES ARE IN CLAMPING RELATIONSHIP, SAID FIRST CONNECTING LEG BEING CONNECTED TO SAID BODY PORTION AT A FIRST POINT AND THE SECOND OF SAID CONNECTION LEGS BEING CONNECTED TO SAID BODY PORTION AT A SECOND POINT, SAID FIRST POINT AND SAID SECOND POINT BEING ADJACENT TO EACH OTHER WHEN SAID EXTREMITIES ARE IN CLAMPING RELATIONSHIP, SAID BODY PORTION FORMING A SUBSTANTIALLY CIRCULAR SHAPE WHEN SAID FIRST POINT IS BROUGHT ADJACENT TO SAID SECOND POINT BY PLACING SAID EXTREMITIES IN CLAMPING RELATIONSHIP AND SAID EXTERMITIES BEING ADAPTED TO BE SECURED TO EACH OTHER WHILE IN CLAMPING RELATIONSHIP. 